American Journal of Microbiological Research
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American Journal of Microbiological Research. 2019, 7(3), 98-101
DOI: 10.12691/ajmr-7-3-5
Open AccessArticle

Assessment of Heterotrophic Bacterial Count (HPC) Associated with Commercial Freezers in Yenagoa Metropolis

Douye V. Zige1, , Faith I. Omeje1 and Christian K. Anumudu1

1Department of Microbiology, Faculty of Science, Federal University, Otuoke, P.M.B. 126, Yenagoa, Bayelsa State, Nigeria

Pub. Date: September 25, 2019

Cite this paper:
Douye V. Zige, Faith I. Omeje and Christian K. Anumudu. Assessment of Heterotrophic Bacterial Count (HPC) Associated with Commercial Freezers in Yenagoa Metropolis. American Journal of Microbiological Research. 2019; 7(3):98-101. doi: 10.12691/ajmr-7-3-5


Microorganism are known to be present anywhere they can proliferate, its presence dictates it pathogenicity or otherwise. The study was embarked to assess the enteric bacterial quality and potential risk of water at the bottom of selected commercial freezers in Yenagoa metropolis. Serial dilution was adopted for the assessment of Heterotrophic bacterial count (HPC). From the analysis, bacterial count ranged between 1.083±0.104×107cfu/mL and 2.0 ± 0.358×107cfu/mL. the highest was in sample 4 (S4) and least in sample 10 (S10), the study thus found the presence of heterotrophic bacteria in all samples. This research reveals that freezers S5, S3, S4 and S8 were seriously contaminated, having mean viable bacterial load of 2.47×107cfu/mL, 2.18×107cfu/mL, 2.00×107 cfu/mL and 2.00×107 cfu/mL, respectively; while freezer S1, S2, S6, S7, S9 and S10 had variably viable bacteria count, the occurrence of heterotrophic bacteria count (HPC) between sampled freezers was statistically very significant (P0.05, 0.01). Bacteria cells using morphological and biochemical characterization identified in the study include Escherichia coli (29.4%), which was the most frequently occurring organism, followed by Citrobacter spp (14.7%), Klebsella pneumonia (14.7%), Shigella spp (11.8%), Pseudomonas aeruginosa (11.8%), Yersinia spp (8.8%) and Campylobacter jejuni (8.8%). E coli were the most frequently isolated bacteria. E. coli and other Eneteric bacteria isolated from freezers are an indication that food items and water stored in these freezers are not safe from public health stand point. Susceptibility of isolates to antibiotics reveals 8(23.5%) were resistant and 26 (76.5%) were susceptible out of 34 cells identified. High resistance was seen in Klebsiella spp which had 2 (60%) and 100% susceptibility was seen among Citrobacter spp and Yersinia spp, on the other hand other isolate had varying drug resistant patterns. The importance of temperature control and regular efficient cleaning regimes need to be communicated to the public so that, effectual management and cleaning of freezers makes frozen food reliable and less likely to act as significant sources of human food and water borne diseases.

Heterotrophic Bacteria Count (HPC) contamination enteric pathogens commercial freezers

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